1. Field of the Invention
The present invention relates to processing carbon-based feedstock, and in particular to an in-feed hopper and meter for feeding feedstock into a distillation chamber.
2. Description of the Related Art
Coal is an abundant natural resource capable of exploitation to produce large amounts of energy. Coal in its raw form, however, usually contains undesirable compositions in the form of a number of other chemical compositions or elements. One problem faced in the coal industry is that traditional means of extracting energy from coal have been the subject of concerns, due to possible adverse environmental consequences because of the undesirable compositions usually present in raw coal. For example, historically coal has been burned to create heat, such as to turn water into steam to power a turbine and generate electricity. This process generates large amounts of gaseous emissions containing small amounts of the undesirable compositions which harm the environment. As a result the use of coal as an energy source can cause tension between, the need for an economic way to produce energy on the one hand, and environmental concerns on the other.
During a typical coal processing operation, coal and other carbon-based products are often subjected to distillation processes in order to extract various products therefrom. Typically, the coal or other carbon-based feedstock is fed directly into a distillation chamber from open, atmospheric hoppers. The feedstock can pass through a meter as it enters the distillation chamber so that the volume of the feedstock entering the distillation chamber is known.
The use of open air hoppers can be problematic became the outside atmosphere contains oxygen. Accordingly, feedstock introduced to a distillation chamber from an open air hopper is often mixed with air containing oxygen. Many distillation processes, however, inhibit oxidation, or the burning of the feedstock during the distillation process, so that the presence of such oxygen in the distillation chamber is problematic.
In addition, much of the raw feedstock supplied to an in-feed hopper is first passed through a grinder, in order to reduce the size of individual units of feedstock so that the feedstock can pass through the hopper and meter more effectively. In some cases, however, pieces of feedstock are introduced to the hopper and meter that were not sufficiently crushed by the grinder, and that are large so that they cannot fit through the meter. Such large pieces of feedstock can become wedged in the meter, binding the meter so that it cannot continue processing the feedstock, and, in some instances, damaging the meter.